[Discuss] GPS feature in cellphones?

[richard.pieri at gmail.com (Richard Pieri)]

Oliver Holmes wrote:
> My question is old voice flip phones could only be traced to the
> transmitting tower. But I understand now that GPS is built in and is
> active whether you activate it or not. So there is the potential to
> track you within three meters. Is this so?

I don't know about the three meter accuracy but yes, every smart phone
and nearly every feature in the US has an always-on positioning
mechanism. This is required by the FCC under the E911 statutes. It's
accurate enough that E911 call centers can provide your location to
within visual range to emergency responders.

Handset makers typically do not provide an option to disable this. On
smart phones it's embedded in the hardware where the OS can't control
it. Disabling location services does not disable the positioning
mechanism; it just tells the OS not to let anything use positioning
data. On feature phones it may be controllable by software but that
software isn't available for devices marked for use in the US and non-US
devices are different enough that their software won't work correctly or
fully on US devices.

A power off state does not disable this "feature" on smart phones and
some feature phones. Either remove the battery or stuff it in a static
bag (Faraday cage). Of course it's not terribly useful as a phone in
that state but at least you have your privacy. :)

-- 
Rich P.